It is known that dialysis is a life-support treatment that uses a special machine to filter harmful wastes, salt, and excess fluid from your blood. This restores the blood to a normal, healthy balance. However the current dialysis can barely replace 10% of renal function. Currently in use Hollow Fiber based Dialysis replaces only limited number of kidney's important functions.
As for liver replacement there is no liver dialysis available. Generally, dialysis works on the principles of the diffusion of solutes and ultrafiltration of fluid across a semi-permeable membrane. Blood flows by one side of a semi-permeable membrane, and a dialysate, or special dialysis fluid, flows by the opposite side. Smaller solutes and fluid pass through the membrane, but the membrane blocks the passage of larger substances, such as red blood cells, large proteins. This replicates the filtering process that takes place in the kidneys, when the blood enters the kidneys and the larger substances are separated from the smaller ones in the glomerulus.
It is known that treatment options for liver disease are limited. Liver transplantation is the favored treatment for serious liver disease or liver failure. However, the number of suitable liver donors varies and is not always sufficient to meet the demand for liver transplant operations. Generally, liver dialysis is a detoxification treatment for liver failure and is currently not available for patients with various liver disorders, such as, for example, hepatorenal syndrome, decompensated chronic liver disease, acute liver failure, graft dysfunction after liver transplantation, liver failure after liver surgery, secondary liver failure and multi organ failure. It is recognized that a critical issue of the clinical syndrome in liver failure is the accumulation of toxins not cleared by the failing liver. Thus, there is a great unmet need for a way to treat patients with liver failure just like kidney failure patients.
Typically, the function of the normal, healthy kidney in the animal body is to act as a filter for the blood circulating through the body, to remove impurities therefrom and restore correct blood composition balance. When the kidneys cease to function, artificial kidneys can be employed in their place, such an artificial kidney comprising a flexible dialysis membrane used outside the body as a separate treatment apparatus for blood dialysis or filtration purposes. One common method for treating failed kidneys involves standard dialysis, in which blood from the body is circulated past one side of the membrane and special dialysis fluid is circulated past the other side of the membrane, so as to adjust and correct the blood composition by osmosis, diffusion, convection, adsorption and ultrafiltration across the membrane. The hepatic toxins are difficult to be removed via dialysis. Also, there is no liver dialysis because liver toxins are protein-bound and are not dialyzeable.
In many instances, patients with one or more failing organs or organ systems would not be able to survive without medical assistance and supportive care. The organs that often fail require life support, however not all organ systems have a replacement or supportive device. The most common types of life support are for the respiratory, cardiovascular, and renal systems. Currently, support systems or replacement systems are non-existent for the liver.
In addition, currently in spite of renal replacement therapies, the favorable outcome of patients with acute kidney failure is less than 50 percent. The mortality even is higher when other organs fail concurrently or sequentially. Multi-Organ Dysfunction Syndrome (MODS) evolves in the wake of a profound disruption of systemic homeostasis. The intriguing concept, hence, of applying more extracorporeal devices for the therapy and support of several organs during (MODS) is appealing and opens the hypothesis of a complex integrated platform that might be defined “multiple organ support therapy” (MOST). At present there is no agent that can reverse the established organ failure.
Therapy therefore is limited to supportive care, i.e. safeguarding hemodynamic, and respiration. Maintaining adequate tissue oxygenation is a principal target. Organ replacement therapy is available for renal failure even though it is not that effective. Even worse, there is no therapy for liver failure except liver transplantation. Mortality of MODS varies from 30% to 100% where the chance of survival is diminished as the number of organs involved increases. Since the 1980s the mortality rate has not changed.
Those skilled in the art, in light of the present teachings, will recognize that microdialysis is a widely employed technique for sampling the chemistry of the extracellular space in vivo. It is unique in its ability to dynamically sample the extracellular fraction of a range of molecules of interest. It has been used in both human and animal studies in the brain and other organs. The technique is now routinely established in several neurointensive care units for bedside monitoring of small molecules related to energy metabolism.
Over recent years, with the advent of membranes with relatively higher molecular weight cut-off (MWCO) dialysis has been drawing wider application with an increasing range of molecules being assayed in the laboratory, including those of higher molecular weights such as cytokines. The relative recovery (RR, also termed extraction efficiency) is defined as the percentage concentration of a molecule in the interstitial fluid (in vivo) or external solution (in vitro) that is collected in the microdialysate.
Other proposals have involved dialysis systems for the liver and kidneys. The problem with these devices is that they do not provide sufficient removal of toxins and water. Thus, an unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies. Even though the above cited methods for dialysis systems meets some of the needs of the market, a combination kidney and liver dialysis system helps remove uremic toxins, hepatic toxins, water, and other impurities from the blood is still desired.